It is well known in the automotive wheel balancing art that to compensate for a static imbalance static imbalance (where the heaviest part of the wheel will seek a position directly below the mounting shaft) or a combination of static imbalance and couple imbalance (where the rotating wheel causes torsional vibrations on the mounting shaft), at least one correction weight is required to be attached to the wheel. Correction weights are commonly positioned along the wheel surface coincident with weight location “planes” that are separated axially, along the wheel surface. For clip-on weights the “left plane” conventionally comprises the left (innermost) rim lip or edge circumference, while the “right plane” comprises the right rim edge. For adhesive weights, the planes can reside anywhere between the rim edges, barring physical obstruction such as wheel spokes and welds.
Existing wheel balancing systems that utilize automatic wheel scanning devices to determine properties of a rim of a wheel (as used herein a wheel includes a rubber tire secured to a metal rim) during a wheel balancing procedure are disclosed in several patents identified and described in the Cullum et al. application, identified above. The Cullum et al. wheel balancer system automatically determines and suggests a proper type of corrective weight to be secured to a wheel rim for appropriate balance by identifying the rim profile of the wheel.
A great variety of wheels having different rim profiles are manufactured by the automotive industry. A wheel balancing technician must have on hand a supply of standardized weights, in a plurality of incremental weight values, that will fit the various types of wheels. Weights are color coded or bear alphanumeric designations in accordance with their weight types. Weights normally are held in pans or color coded bins. At present, cumulative tracking of corrective weight usage during time periods in which several wheel balancing procedures have been performed is not determined with accuracy without a personal counting of the individual weights that remain. Weight inventory thus is a problem for the wheel balance technician, especially so for high volume tire dealers. Typically, the dealer monthly will place a blanket purchase order of all weight sizes and types. Over time, a large inventory will be built up of weights for which there has been little or no usage. Conversely, the inventory may run out of weights of high usage.
The need thus exists to track the corrective weights that have been applied during all wheel balancing operations. If the user can be provided an accurate account of specific weight usage during a given period, weight purchase orders can be formulated that are concentrated in proportion to the tracked usage. Such a tracking system would be of further benefit if it could provide the user with notification when the stock on hand of particular weights are low.